Black

for mourning was a Roman custom (Juvenal, x. 245)
borrowed from the Egyptians.

Black,

in blazonry, means constancy, wisdom, and prudence. Black,
in several of the Oriental nations, is a badge of servitude, slavery,
and low birth. Our word blackguard seems to point to this
meaning. The Latin niger meant bad, unpropitious. (See
Blackguard.)